[Follow-up study on prevalence rate of congenital defects in children at birth and age of two years].

To obtain prevalence rate of congenital defects during age of two years 16107 children were followed. Our data demonstrate that the prevalence rate of over all congenital defects at birth increased about 69% compared with at age of two years. The reason for prevalence rate increasing with age was that many children with internal organ defects were not diagnosed until three months or later. Prevalence rate of congenital heart disease at birth was approximately one-fifth of that at age of two years. For gastrointestinal and abdominal wall defects, the prevalence rate increased about 1.5 fold. This two sorts of defects above-mentioned were number eight and number five among over all defects at birth respectively. Three months after birth they became number one and number two.